Muscle Size and Strength: Understanding the Difference
By Katie Kissane MS, RD, CSSD
Muscles are the most adaptable tissue in the human body. The term bodybuilding exemplifies this. But muscle size and strength are not one in the same. Muscle size can influence strength, but muscle strength does not always predict size. This means that someone with larger muscles may not necessarily be able to lift more weight than a person with smaller muscles. There are a lot of factors that contribute to strength beyond muscle mass and muscle size.
What Influences Muscle Strength?
Muscle strength is determined by many factors, including:
- Size and type of muscle fibers, and the nerves that activate them
- Stretch of the muscle
- Speed of muscle contraction
- Limb and muscle length
- Hormones (testosterone and androgens)
- Type of exercise performed
What Influences Muscle Size?
Muscle growth and size (also known as hypertrophy) is related to an increase in water, number of muscle fibers, and connective tissue. Just as with strength, factors such as hormone levels and gender will have a varying effect on the extent of muscle size. A person wanting to have muscle size may train differently than a person looking to gain strength.
Training for Muscle Size vs. Strength
Of course, nobody is going to have an increase in muscle size or strength without proper training. Resistance training results in mild damage to the muscle fibers. This injury prompts signals from the cells that bring about a cascade of events leading to muscle repair and growth. Muscle growth occurs when the rate of muscle protein building is greater than the rate of protein breakdown.
Training for muscle size may involve more volume with less weight (or load) as compared with training for strength. Training for strength often involves larger movements working several muscles at one time, while training for size may involve training one muscle or group of muscles in isolation. Of course, training programs for both muscle size and strength depend on the training cycle and specific goals of the individual.
Fueling Your Muscles
Many of the factors that contribute to muscle size and strength are not under our control. We can’t change genetics, age or limb length. Through proper resistance training, we can provide the stimulus for muscle growth—but without the building blocks for muscle repair and building, the muscles can’t increase in strength or size.
Protein plays a direct role in muscle building and repair, but there are other nutrients that play a more supportive role. Carbohydrates, when consumed post-resistance exercise, help stimulate the recovery process.
Before Your Workout
For both muscle growth and increased strength, it is a good idea to have a meal consisting of protein, carbohydrate, and fat. About 20-30 grams of protein is ideal. If you are strapped for time prior to your workout, you can always grab a protein bar that contains both protein and carbohydrate.
You could also choose a pre-workout formula or electrolyte drink that contains caffeine. Caffeine’s stimulatory effect can be a great pre-workout booster. If you are going into a workout in a fasted state (without a meal), you may want to consider taking a branched chain amino acid (BCAA).
During the Workout
Unless you are working out for longer than 60 minutes, there might not be much benefit from consuming anything beyond water. If you’re working out for longer than 60 minutes, a simple electrolyte drink can be beneficial to help replenish electrolytes.
After the Workout
Consuming carbohydrates and protein is helpful for recovery after a workout. Protein powders can be beneficial in this regard. A good quality whey protein powder will have all of the essential amino acids, including branched chain, but it might be beneficial to also add a BCAA supplement. Protein bars can work great here, too.
Supplements to Support Muscle Strength and Size
Beta-alanine can help buffer acid in the muscle. Many people report being able to increase the number of reps they can do in the gym when taking this supplement. The increase in reps can translate to more muscle strength and size over time. The standard daily dose is 2-5 grams, taken 2-3 times during the day.
Creatine monohydrate is a molecule that can rapidly produce energy (as ATP), which can aid cellular function during stress. Creatine monohydrate is the cheapest and most effective type of creatine. The typical loading protocol is .3 g/kg for 5-7 days, then .03 g/kg for about three weeks (if cycling) or indefinitely.